Deck 6: External Memory

Question 1

The width of a track is double that of the head.

Answer 1

False

Question 2

There are typically hundreds of sectors per track and they may be either fixed or variable lengths.

Answer 2

True

Question 3

Greater ability to withstand shock and damage,improvement in the uniformity of the magnet film surface to increase disk reliability,and a significant reduction in overall surface defects to help reduce read-write errors,are all benefits of ___________.

A)magnetic read and write mechanisms
B)platters
C)the glass substrate
D)a solid state drive

Answer 3

C

Question 4

In most contemporary systems fixed-length sectors are used,with _________ bytes being the nearly universal sector size.

A)64
B)128
C)256
D)512

Question 5

A removable disk can be removed and replaced with another disk.

Question 6

Data are transferred to and from the disk in __________.

A)tracks
B)gaps
C)sectors
D)pits

Question 7

A bit near the center of a rotating disk travels past a fixed point slower than a bit on the outside.

Question 8

Because data are striped in very small strips,RAID 3 cannot achieve very high data transfer rates.

Question 9

Adjacent tracks are separated by _________.

A)sectors
B)gaps
C)pits
D)heads

Question 10

Flash memory becomes unusable after a certain number of writes.

Question 11

Scanning information at the same rate by rotating the disk at a fixed speed is known as the _________.

A)constant angular velocity
B)magnetoresistive
C)rotational delay
D)constant linear velocity

Question 12

SSD performance has a tendency to speed up as the device is used.

Question 13

The disadvantage of using CAV is that individual blocks of data can only be directly addressed by track and sector.

Question 14

Magnetic disks are the foundation of external memory on virtually all computer systems.

Question 15

RAID level 0 is not a true member of the RAID family because it does not include redundancy to improve performance.

Question 16

During a read or write operation,the head rotates while the platter beneath it stays stationary.

Question 17

RAID is a set of physical disk drives viewed by the operating system as a single logical drive.

Question 18

The SSDs now on the market use a type of semiconductor memory referred to as flash memory.

Question 19

The transfer time to or from the disk does not depend on the rotation speed of the disk.

Question 20

The head must generate or sense an electromagnetic field of sufficient magnitude to write and read properly.

Question 21

A __________ disk is permanently mounted in the disk drive,such as the hard disk in a personal computer.

A)nonremovable
B)movable-head
C)double sided
D)removable

Question 22

The sum of the seek time and the rotational delay equals the _________,which is the time it takes to get into position to read or write.

A)access time
B)gap time
C)transfer time
D)constant angular velocity

Question 23

Data is organized on the platter in a concentric set of rings called ________.

Question 24

__________ is the standardized scheme for multiple-disk database design.

A)RAID
B)CAV
C)CLV
D)SSD

Question 25

The disadvantage of _________ is that the amount of data that can be stored on the long outer tracks is only the same as what can be stored on the short inner tracks.

A)SSD
B)CAV
C)ROM
D)CLV

Question 26

To increase density in a straightforward CAV system,modern hard disk systems use a technique known as __________,in which the surface is divided into a number of concentric zones.

Question 27

________ is when the disk rotates more slowly for accesses near the outer edge than for those near the center.

A)Constant angular velocity (CAV)
B)Magnetoresistive
C)Constant linear velocity (CLV)
D)Seek time

Question 28

__________ heads are used in sealed drive assemblies that are almost free of contaminants and the head is actually an aerodynamic foil that rests lightly on the platter's surface when the disk is motionless.

Question 29

The set of all the tracks in the same relative position on the platter is referred to as a _________.

A)floppy disk
B)single-sided disk
C)sector
D)cylinder

Question 30

On a movable-head system,the time it takes to position the head at the track is known as __________.

Question 31

RAID level ________ has the highest disk overhead of all RAID types.

A)0
B)1
C)3
D)5

Question 32

Data are recorded on and later retrieved from the disk via a conducting coil named the _________.

Question 33

The areas between pits are called _________.

A)lands
B)sectors
C)cylinders
D)strips

Question 34

The time required to move the disk arm to the required track is the __________.

Question 35

The _________ disk is a small,flexible platter and the least expensive type of disk.

Question 36

When the magnetizable coating is applied to both sides of the platter the disk is then referred to as _________.

A)multiple sided
B)substrate
C)double sided
D)all of the above

Question 37

A __________ is a circular platter constructed of nonmagnetic material,called the substrate,coated with a magnetizable material.

Question 38

In a __________ disk there is only one read-write head mounted on an arm that can be extended or retracted to be able to be positioned above any track.

Question 39

In a _________ disk there is one read-write head per track and all of the heads are mounted on a rigid arm that extends across all tracks.

Question 40

A _________ is a high-definition video disk that can store 25 Gbytes on a single layer on a single side.

A)DVD
B)DVD-R
C)DVD-RW
D)Blu-ray DVD

Question 41

RAID levels 4 through 6 make use of an __________ access technique that allows separate I / O requests to be satisfied in parallel.

Question 42

RAID levels 2 and 3 make use of a _________ access technique in which all member disks participate in the execution of every I / O request.

Question 43

A _________ drive is a memory device made with solid-state components that can be used as a replacement to a hard disk drive.

Question 44

The _________ strategy employs multiple disk drives and distributes data in such a way as to enable simultaneous access to data from multiple drives,thereby improving I / O performance and allowing easier incremental increases in capacity.

Question 45

The typical recording technique used in serial tapes is referred to as _________ recording.